As with many consumer products electrical appliances are subject to rules, regulations, and laws which attempt to ensure product quality and user safety. For example, UL 858 is a set of safety standards which apply to electrically operated household cooking appliances such as cooktops, ovens, stoves, ranges, etc. According to UL 858, a household cooking appliance must pass a high potential voltage test prior to being sold to a consumer. The high potential voltage test has to be conducted after the household cooking appliance is fully assembled. Unfortunately, implementing the high potential test can be problematic because many cooking appliances include electrical components which are designed to prevent voltages which fall in the range of the test.
For example, many modern cooking appliances include one or more metal oxide varistors (MOVs) on their power supplies to suppress high voltage transients which can occur during power surges, lightning storms, etc. To protect the cooking appliance and its user, the MOVs prevent high input voltages such as those in the range of the required high potential test. Cooking appliance manufacturers address this problem by disconnecting the MOVs from a constant earth ground to which the rest of the cooking appliance is connected. Without the constant earth ground, the MOVs are able to float such that an apparent voltage differential caused by the high potential input is minimal. In traditional cooking appliances, connecting and/or disconnecting the MOVs to the electrical ground requires that the cooking appliance be disassembled.
Thus, implementing a simple high potential test can require that the cooking appliance be assembled and disassembled multiple times. For example, the cooking appliance manufacturer has to fully assemble the cooking appliance with the MOV(s) disconnected perform the high potential test by sending a voltage through the electrical appliance, disassemble the cooking appliance, manually connect the MOV(s) to the electrical ground connected to the rest of the cooking appliance, and reassemble the cooking appliance, all prior to packaging the cooking appliance. This process is laborious and time consuming and results in lost revenue for the cooking appliance manufacturer,
Thus, there is a need for an electrical appliance which includes an external grounding mechanism such that an MOV or other electrical component can be connected to and/or disconnected from an electrical ground without disassembling the electrical appliance.